Running costs vary wildly between car models

When asked how much they spent on motoring a year, drivers underestimated the costs by more than �3,000 on average, the RAC added.

Car running costs are increasing, the RAC warned, because of increases in the price of petrol and greater depreciation costs.

Overall, running costs can vary by up to �250 a week between car models.

Expensive

According to the RAC, large cars such as the BMW 7 series and the Land Rover Discovery are among the most expensive to run.

Factoring in depreciation, fuel, insurance, maintenance, road tax, recovery services and loan costs a new BMW 7 Series costs on average �16,352 to run a year.

Average running costs by model BMW 7 Series �16,352 Land Rover Discovery �8,253 Ford Focus �5,302 Vauxhall Corsa �4,153 Toyota Yaris �3,281 Source: RAC

At the other end of the scale, small cars such as the Toyota Yaris and Vauxhall Corsa cost �3,281 and �4,153 respectively.

Nevertheless Britons seem undaunted by the cost of running their pride and joy.

RAC said that up to three quarters of motorists would refuse to change their driving habits to save on fuel.

In addition, most motorists said that they would be prepared to pay up to �1,400 a year more rather than moving to a fuel efficient model.

"Not only do we underestimate how much our cars cost to run, even when we do know, most of us are prepared to pay much more before giving up our motoring habit," Nina Arnott RAC Insure spokeswoman said.

The RAC research coincides with the launch of new car registrations on 1 March.